Automatic merge from submit-queue

refactor getPidsForProcess and change error handling

xref https://github.com/openshift/origin/issues/13262

Right now, failure to read the docker pid from the pid file results in some premature nasty logging.  There is still a chance we can get the docker pid from `procfs.PidOf()`.  If that fails we should just log at `V(4)` rather than `runtime.HanldeError()`.

This PR refactors `getPidsForProcess()` to wait until both methods for determining the pid fail before logging anything.

@smarterclayton @ncdc @derekwaynecarr